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Metacarpal Bone
In human anatomy, the metacarpal bones or metacarpus, also known as the "palm bones", are the appendicular bones that form the intermediate part of the hand between the phalanges (fingers) and the carpal bones ( wrist bones), which articulate with the forearm. The metacarpal bones are homologous to the metatarsal bones in the foot. Structure The metacarpals form a transverse arch to which the rigid row of distal carpal bones are fixed. The peripheral metacarpals (those of the thumb and little finger) form the sides of the cup of the palmar gutter and as they are brought together they deepen this concavity. The index metacarpal is the most firmly fixed, while the thumb metacarpal articulates with the trapezium and acts independently from the others. The middle metacarpals are tightly united to the carpus by intrinsic interlocking bone elements at their bases. The ring metacarpal is somewhat more mobile while the fifth metacarpal is semi-independent.Tubiana ''et al'' 1998, p 11 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpal Bones
The carpal bones are the eight small bones that make up the wrist (carpus) that connects the hand to the forearm. The terms "carpus" and "carpal" are derived from the Latin wikt:carpus#Latin, carpus and the Greek language, Greek wikt:καρπός#Ancient Greek, καρπός (karpós), meaning "wrist". In human anatomy, the main role of the carpal bones is to joint, articulate with the radius (bone), radial and ulnar heads to form a highly mobile condyloid joint (i.e. wrist joint),Kingston 2000, pp 126-127 to provide attachments for thenar and hypothenar muscles, and to form part of the rigid carpal tunnel which allows the median nerve and tendons of the anterior compartment of the forearm, anterior forearm muscles to be transmitted to the hand and fingers. In tetrapods, the carpus is the sole cluster of bones in the wrist between the radius (bone), radius and ulna and the metacarpus. The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foot
The foot (: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is an organ at the terminal part of the leg made up of one or more segments or bones, generally including claws and/or nails. Etymology The word "foot", in the sense of meaning the "terminal part of the leg of a vertebrate animal" comes from Old English ''fot'', from Proto-Germanic *''fot'' (source also of Old Frisian ''fot'', Old Saxon ''fot'', Old Norse ''fotr'', Danish ''fod'', Swedish ''fot'', Dutch ''voet'', Old High German ''fuoz'', German ''Fuß'', Gothic ''fotus'', all meaning "foot"), from PIE root *''ped-'' "foot". The plural form ''feet'' is an instance of i-mutation. Structure The human foot is a strong and complex mechanical structure containing 26 bones, 33 joints (20 of which are actively articulated), and more than a hundred muscles, tendons, and ligaments.Podiatry Chan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First Metacarpal Bone
The first metacarpal bone or the metacarpal bone of the thumb is the first bone proximal to the thumb. It is connected to the trapezium of the carpus at the first carpometacarpal joint and to the proximal thumb phalanx at the first metacarpophalangeal joint. Characteristics The first metacarpal bone is short and thick with a shaft thicker and broader than those of the other metacarpal bones. Its narrow shaft connects its widened base and rounded head; the former consisting of a thick cortical bone surrounding the open medullary canal; the latter two consisting of cancellous bone surrounded by a thin cortical shell. Head The head is less rounded and less spherical than those of the other metacarpals, making it better suited for a hinge-like articulation. The distal articular surface is quadrilateral, wide, and flat; thicker and broader transversely and extends much further palmarly than dorsally. On the palmar aspect of the articular surface there is a pair of emin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carpometacarpal Joint
The carpometacarpal (CMC) joints are five joints in the wrist that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones. The CMC joint of the thumb or the first CMC joint, also known as the trapeziometacarpal (TMC) joint, differs significantly from the other four CMC joints and is therefore described separately. Thumb The carpometacarpal joint of the thumb (''pollex''), also known as the first carpometacarpal joint, or the trapeziometacarpal joint (TMC) because it connects the trapezium to the first metacarpal bone, plays an irreplaceable role in the normal functioning of the thumb. The most important joint connecting the wrist to the metacarpus, osteoarthritis of the TMC is a severely disabling condition; it is up to twenty times more common among elderly women than in the average. Pronation-supination of the first metacarpal is especially important for the action of opposition. The movements of the first CMC are limited by the sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpophalangeal Joint
The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the proximal phalanges. Being condyloid, they allow the movements of flexion, extension, abduction, adduction and circumduction (see anatomical terms of motion) at the joint. Structure Ligaments Each joint has: * palmar ligaments of metacarpophalangeal articulations * collateral ligaments of metacarpophalangeal articulations Dorsal surfaces The dorsal surfaces of these joints are covered by the expansions of the Extensor tendons, together with some loose areolar tissue which connects the deep surfaces of the tendons to the bones. Function The movements which occur in these joints are flexion, extension, adduction, abduction, and circumduction; the movements of abduction and adduction are very ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extensor Muscle
In anatomy, extension is a movement of a joint that increases the angle between two bones or body surfaces at a joint. Extension usually results in straightening of the bones or body surfaces involved. For example, extension is produced by extending the flexed (bent) elbow. Straightening of the arm would require extension at the elbow joint. If the head is tilted all the way back, the neck is said to be extended. Extensor muscles Upper limb *of arm at shoulder **Axilla and shoulder ***Latissimus dorsi *** Posterior fibres of deltoid *** Teres major *of forearm at elbow **Posterior compartment of the arm ***Triceps brachii *** Anconeus *of hand at wrist ** Posterior compartment of the forearm *** Extensor carpi radialis longus *** Extensor carpi radialis brevis *** Extensor carpi ulnaris *** Extensor digitorum *of phalanges, at all joints ** Posterior compartment of the forearm *** Extensor digitorum *** Extensor digiti minimi (little finger only) *** Extensor indicis (index f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpophalangeal
The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the proximal phalanges. Being condyloid, they allow the movements of flexion, extension, abduction, adduction and circumduction (see anatomical terms of motion) at the joint. Structure Ligaments Each joint has: * palmar ligaments of metacarpophalangeal articulations * collateral ligaments of metacarpophalangeal articulations Dorsal surfaces The dorsal surfaces of these joints are covered by the expansions of the Extensor tendons, together with some loose areolar tissue which connects the deep surfaces of the tendons to the bones. Function The movements which occur in these joints are flexion, extension, adduction, abduction, and circumduction; the movements of abduction and adduction are very ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proximal Phalanx
The phalanges (: phalanx ) are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges. The phalanges are classed as long bones. Structure The phalanges are the bones that make up the fingers of the hand and the toes of the foot. There are 56 phalanges in the human body, with fourteen on each hand and foot. Three phalanges are present on each finger and toe, with the exception of the thumb and big toe, which possess only two. The middle and far phalanges of the fifth toes are often fused together (symphalangism). The phalanges of the hand are commonly known as the finger bones. The phalanges of the foot differ from the hand in that they are often shorter and more compressed, especially in the proximal phalanges, those closest to the torso. A phalanx is named according to whether it is proximal, middle, or distal and its associated finger or toe. The proximal phalange ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ligament
A ligament is a type of fibrous connective tissue in the body that connects bones to other bones. It also connects flight feathers to bones, in dinosaurs and birds. All 30,000 species of amniotes (land animals with internal bones) have ligaments. It is also known as ''articular ligament'', ''articular larua'', ''fibrous ligament'', or ''true ligament''. Comparative anatomy Ligaments are similar to tendons and fasciae as they are all made of connective tissue. The differences among them are in the connections that they make: ligaments connect one bone to another bone, tendons connect muscle to bone, and fasciae connect muscles to other muscles. These are all found in the skeletal system of the human body. Ligaments cannot usually be regenerated naturally; however, there are periodontal ligament stem cells located near the periodontal ligament which are involved in the adult regeneration of periodontist ligament. The study of ligaments is known as . Humans Other ligame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray's Anatomy
''Gray's Anatomy'' is a reference book of human anatomy written by Henry Gray, illustrated by Henry Vandyke Carter and first published in London in 1858. It has had multiple revised editions, and the current edition, the 42nd (October 2020), remains a standard reference, often considered "the doctors' bible". Earlier editions were called ''Anatomy: Descriptive and Surgical'', ''Anatomy of the Human Body'' and ''Gray's Anatomy: Descriptive and Applied'', but the book's name is commonly shortened to, and later editions are titled, ''Gray's Anatomy''. The book is widely regarded as an extremely influential work on the subject. Publication history Origins The English anatomist Henry Gray was born in 1827. He studied the development of the endocrine glands and spleen and in 1853 was appointed Lecturer on Anatomy at St George's Hospital Medical School in London. In 1855, he approached his colleague Henry Vandyke Carter with his idea to produce an inexpensive and access ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metacarpophalangeal Joints
The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow cavities on the proximal ends of the proximal phalanges. Being condyloid, they allow the movements of flexion, extension, abduction, adduction and circumduction (see anatomical terms of motion) at the joint. Structure Ligaments Each joint has: * palmar ligaments of metacarpophalangeal articulations * collateral ligaments of metacarpophalangeal articulations Dorsal surfaces The dorsal surfaces of these joints are covered by the expansions of the Extensor tendons, together with some loose areolar tissue which connects the deep surfaces of the tendons to the bones. Function The movements which occur in these joints are flexion, extension, adduction, abduction, and circumduction; the movements of abduction and adduction are very ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Interossei Of The Hand
In human anatomy, the dorsal interossei (DI) are four muscles in the back of the hand that act to abduct (spread) the index, middle, and ring fingers away from the hand's midline (ray of middle finger) and assist in flexion at the metacarpophalangeal The metacarpophalangeal joints (MCP) are situated between the metacarpal bones and the proximal phalanges of the fingers. These joints are of the condyloid kind, formed by the reception of the rounded heads of the metacarpal bones into shallow ... joints and extension at the interphalangeal joints of the index, middle and ring fingers. Structure There are four dorsal interossei in each hand. They are specified as 'dorsal' to contrast them with the palmar interossei, which are located on the anterior side of the metacarpals. The dorsal interosseous muscles are bipennate, with each muscle arising by two heads from the adjacent sides of the metacarpal bones, but more extensively from the metacarpal bone of the finger into whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
